Delhi's winter air pollution

Critical severity. Severe, persistent harm to health, ecosystems or livelihoods. Severity is descriptive editorial metadata summarising documented effects. It is not a measured index or a score.

1. 01

   Winter meteorology over the Indo-Gangetic Plain

   Cold, still air and shallow mixing depth trap emissions near ground level.

2. 02

   Crop residue burning in neighbouring states

   Post-monsoon stubble burning produces smoke that is transported into the region.

3. 03

   Transport emissions

   A very large vehicle fleet in a sprawling metropolitan region emits particulates and precursor gases.

4. 04

   Construction and road dust

   Continuous construction activity and unpaved surfaces contribute coarse and fine dust.

5. 05

   Industry, waste burning and domestic fuel

   Industrial combustion, open waste burning and solid fuel use for cooking and heating add to the load.

1. 01

   Severe health burden

   Exposure to very high fine particulate concentrations is linked to respiratory disease, cardiovascular disease and premature mortality.

2. 02

   School closures and restricted activity

   Emergency measures during severe episodes include closing schools and halting construction.

3. 03

   Economic cost

   Health care costs, lost working days and reduced productivity accompany prolonged pollution episodes.

4. 04

   Reduced visibility

   Dense haze disrupts road, rail and air transport during peak episodes.

1. Graded Response Action Plan

   A staged set of emergency measures triggered automatically as air quality deteriorates.

   Expected effectReduces some emissions during peak episodes; it is a response mechanism, not a structural fix.

2. Crop residue management

   Machinery, incentives and alternative uses to avoid burning stubble in neighbouring states.

   Expected effectAddresses a major seasonal regional contribution; requires sustained inter-state programmes.

3. Fuel and vehicle standards

   Bharat Stage VI fuels and vehicles, CNG fleets and electrification of public transport.

   Expected effectStructurally reduces transport emissions as the fleet turns over.

4. Dust control on construction and roads

   Site covering, water spraying, mechanised sweeping and paving of shoulders.

   Expected effectReduces the coarse and fine dust fraction of local pollution.

5. Airshed-level governance

   Coordinated management across the National Capital Region rather than city boundaries alone.

   Expected effectMatches the scale of policy to the scale of the pollution problem.

WHO annual PM2.5 guideline

5µg/m³2021

Delhi's monitored winter concentrations are documented at many times this guideline; consult CPCB monitoring for current values.

Emergency framework

Graded Response Action Plan

A staged response plan triggered by measured air quality index thresholds across the National Capital Region.

1. [1]Graded Response Action PlanCommission for Air Quality Management in the NCR, Indiacaqm.nic.in(opens in a new tab)
2. [2]National Air Quality Index and monitoring dataCentral Pollution Control Board, Indiacpcb.nic.in(opens in a new tab)
3. [3]WHO global air quality guidelinesWorld Health Organization · Sept 2021who.int(opens in a new tab)

Links open the publishing organisation's site. Some point to the publisher's main page, where the named report or dataset can be found.